july in your garden : SUMMER'S LOVELIEST TREE

If you live where coastal fogs will disappear for the summer later this month, well away from the beach, you can grow one of the prettiest of all trees--the crape myrtle, Lagerstroemia indica . Where fogs linger, crape myrtles tend to mildew badly (although there is news on this front) and flower poorly. But in the inland valleys--San Fernando, Simi, Santa Clarita, San Gabriel, Pomona--and in the Riverside-San Bernardino area or in the Escondido area of San Diego County, it would be a shame to have a garden that didn't include a crape myrtle. They are spectacular at all times of the year.

Even in winter, crape myrtles are things of beauty--their bark smooth, gray with a pink blush, their branches a dainty silhouette against the sky. In spring, the new foliage is a dramatic reddish bronze, and in the fall, it turns an orange-yellow or crimson color.

The crape-like flowers begin about now, and the last petals fall in early autumn. Pictured at left are the brilliant red Cherokee (far left), the pink and white Peppermint Lace (just below) and the hot pink Catawba (at right). Cherokee and Catawba were developed at the National Arboretum and were selected partly because of their supposed resistance to mildew. That means they may succeed in areas where fog penetrates but where days are generally hot, such as in downtown Los Angeles or in the Anaheim-Santa Ana area. There are also crape myrtles that are colored in white and orchid.

Now is a fine time to plant. Most crape myrtles grow into upright trees of about 30 feet, but there are also shrub-sized versions, such as the Petite series, that can even be grown in a pot.

FOR FLOWERS RIGHT AWAY

As perennials continue to gain favor with gardeners, yarrows have to rate among the most rewarding and least demanding.

A mainstay in herbaceous borders, the fernleaf yarrow ( Achillea filipendulina ), at left, is valuable both for color and for cutting (fresh or dried). It grows to a height of five feet, so its bright yellow, flattish flower heads may require staking. Blooms appear from spring to midsummer and combine well with salvia, dusty miller and Shasta daisies.

Silvery yarrow ( Achillea clavennae ) is much shorter, reaching a height of only 5 to 10 inches, and is more at home with similar Mediterranean-looking plants--between pavers or as an edging. Its deeply lobed, silvery leaves hug the ground, while loose clusters of flat-topped, white, 3/4-inch blooms float above.

Yarrows flourish in full sun and require no special soil. Once established, they need only moderate amounts of water. Few pests, other than snails and slugs, are attracted to them. Like most perennials, the best time to plant is in the fall. However, plants are usually available only in the spring and summer, when they are in bloom. If you purchase them now, plant them temporarily in a place where you can provide them with careful watering. Then in the fall, divide them into small clumps, allowing each to retain some roots. When grown from seed, yarrows usually produce blooms in their second year.

Fuchsia Warning

The fuchsia mite ( Aculops fuchsiae ), first spotted in Northern California in 1981, has now been reported in Southern California--specifically in Palos Verdes and just this spring in Pacific Palisades and Ventura. This eriophyid mite infests fuchsias, grotesquely distorting foliage and buds and creating the appearance of peach-leaf curl.

In laboratory tests, the fuchsia mite has been controlled by applications of Diazinon and Sevin. However, eradication is quite difficult, and home gardeners are advised to destroy infested plants by sealing them carefully in plastic bags and discarding them in trash cans.

The fuchsia mite is spread by plant-to-plant contact, insects, hummingbirds, air currents and fuchsia collectors. Because the incubation period can be as long as three months, evidence of the mite is not always discernible. Therefore, buy fuchsias only from nurseries that keep their plants in the best of shape. Do not accept gift fuchsias unless you are certain that they are free of mites.